Abstract

Populations of seven Ancistrus species were analyzed from streams and rivers of three hydrographic Brazilian basins. All populations showed different diploid numbers (2n), fundamental numbers (FNs), and karyotypes. Some representatives of Loricariidae have 2n = 54 chromosomes, which is very likely an ancestral cytotaxonomic characteristic, but many other representatives show extensive karyotype diversification. In the Ancistrus species studied, extensive karyotypic differentiation, which is generally associated with chromosome number reduction and rearrangement of the ribosomal RNA gene (rDNA) sites, was verified. Chromosomal locations of 18S and 5S rDNA were jointly detected using fluorescence in situ hybridization (FISH). In all the Ancistrus species analyzed, 18S rDNA sites were detected only on one chromosome pair, though this differed among species. 5S rDNA was located on 1–3 chromosome pairs either separately or in synteny with 18S rDNA in four of the seven species/populations. Hence the karyotype differentiation in Ancistrus species could be associated with a morphological speciation process, suggesting that chromosome fusions, inversions, deletions, duplications, and heterochromatination could contribute to the karyotype evolution of these neotropical armored catfishes.

Addeddate

2025-03-14 00:54:01

Bhl_virtual_titleid

210879

Bhl_virtual_volume

v.5:no.4 (2011)

Call number

10_3897_compcytogen_v5i4_1757

Call-number

10_3897_compcytogen_v5i4_1757

Foldoutcount

0

Genre

article

Identifier

chromosomaldive5mari

Identifier-ark

ark:/13960/s2k2kr572x5

Identifier-bib

10_3897_compcytogen_v5i4_1757

Identifier-doi

10.3897/compcytogen.v5i4.1757

Issue

4

Ocr

tesseract 5.3.0-6-g76ae

Ocr_detected_lang

en

Ocr_detected_lang_conf

1.0000

Ocr_detected_script

Latin

Ocr_detected_script_conf

1.0000

Ocr_module_version

0.0.21

Ocr_parameters

-l eng

Page_number_confidence

84

Page_number_module_version

1.0.5

Page_range

289-300

Pages

12

Pdf_degraded

invalid-jp2-headers

Pdf_module_version

0.0.25

Possible copyright status

In copyright. Digitized with the permission of the rights holder.

Ppi

300

Source

Comparative Cytogenetics 5(4)

Year

2011

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